Well I slipped up and bought a used D3s. I had planned to either sell my d750 or d3s, whichever moved me less but now I don't want to ditch either. The D3s files just look better to me. I shoot in RAW and somehow the colors from the d3s look a lot better, more vibrant than the 750. I thought maybe the d3s files might look better because my computer is about the same age as a d3s?? just a thought. The D3s focusing seems better than the 750. Apparently there is a ton of new tech in the 750 which is supposed to make it focus faster and better but from my experience the d3s wins in focusing. Also the big bad buffer on the d3S is amazing as well as the 9fps. Where the D750 wins is macro, cropping and printing. Obviously the 24mp allows much cropping to be done as well as macro resolution is phenomenal .The prints that I have done with the D750 look drop dead amazing the prints I have done with the d3s may take some tweaking in post to get them where I want them to be....anyways, that's just an update from the NAS front. Here are some images from a local Hispanic Heritage Festival taken with the D3s and a 70-300 4.5-5.6 .

Pairing the D750 with a D3s was for sure a good choice (i did something similar by pairing the D3s with a D3x). For me this (or any similar combo) is the perfect setup when i shoot events having the D3s with the 24-70 and the D3x with the 70-200 2.8. Later cropping the D3x images (when needed) to get closer and resizing to the same size of the D3s files is the most flexibel setup for me. Especially at times, when the "extra reach" is unexpectedly needed (in any other case I´d bring the 200-400 anyway).

One Q: How hard is it for you in busy situations to switch from one body to the other as they´re very different in handling?

Well I haven't had both going in busy situation yet but I do wish the d3s had another way of setting ISO other than the back button. I have my d750 set up so that the video record button operates as an ISO button which is awfully nice.